Valve train of engine for vehicle

ABSTRACT

A valve train of an engine for a vehicle may include a rocker arm that reciprocates up and down, a valve bridge that is moved by the rocker arm and operates a valve installed in a combustion chamber, and a member for rotating valve interposed between the valve bridge and a valve spring disposed at an upper part of the valve. The valve train rotates the valve by a predetermined angle when the valve reciprocates.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims priority of Korean Patent Application Number 10-2013-0156679 filed on Dec. 16, 2013, the entire contents of which application are incorporated herein for all purposes by this reference.

BACKGROUND OF INVENTION

1. Field of Invention

The present invention relates to a valve train of an engine for a vehicle, and more particularly, to a valve train of an engine for a vehicle which prevents the one-side wear or the deformation due to an uneven contact between a valve and a valve seat by facilitating the rotation of the valve, and by being functioned as a retainer simultaneously.

2. Description of Related Art

In general, when opening and closing a valve, the force of a valve spring is directly transferred to the contact surface of a retainer, the relative frictional force is great in this process, the valve spring moves together with a valve system.

When a longitudinal displacement is exerted on the valve spring, it causes twisting force on a coil, and an angular displacement (rotation) is exerted on the spring, and simultaneously, the angular displacement is also exerted on the valve system.

However, in case that the inertial acceleration is not large due to high engine speed, it is difficult for the valve system and the valve to rotate reciprocally. When the valve spring is restored to its original position after being rotated, the valve is also restored to its original position after being rotated during being lifted.

Accordingly, the valve does not rotate, in this case the contact position between the valve and the valve seat does not change, and they continually contact on the same position as such, which results in problems such as one-side wear, deformation or gas leakage, and so on.

And, when the gas leakage occurs, the valve is melt down due to overheat of the exhaust valve, and the combust and exhaust gas is also flowed in an intake valve, which deteriorates the combustion, and consequently has bad effect on the emission and the power.

Also, the knocking is occurred since the combustion is improperly done due to the decline of compressive pressure, and the problem such as the melting of the piston may occur.

To solve such problems, a method is considered which uses a multiple groove cotter to make easy the rotation of the valve. However, this does not induce the reciprocal rotation forcibly, but is devised to decrease the relative frictional force only in case of the reciprocal rotation of the valve, which is hard to get effect unless the rpm of the engine or the inertial force of the valve system is great.

The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

SUMMARY OF INVENTION

The present invention relates to a valve train of an engine for a vehicle which prevents the one-side wear or the deformation due to an uneven contact between a valve and a valve seat by facilitating the rotation of the valve, and by being functioned as a retainer simultaneously.

According to various aspects, a valve train of an engine for a vehicle may include a rocker arm that reciprocates up and down, a valve bridge that is moved by the rocker arm and operates a valve installed in a combustion chamber, and a member for rotating valve interposed between the valve bridge and a valve spring disposed at an upper part of the valve, wherein the member for rotating valve rotates the valve with a predetermined angle when the valve reciprocates.

The member for rotating valve may include a valve cotter engaged with an upper exterior circumference of the valve, a retainer body engaged with an exterior circumference of the valve cotter, a collar spaced apart from an exterior circumference of the retainer body, wherein an lower end is fixedly supported by the valve spring, and an elastic member interposed between the retainer body and the collar, wherein one end is fixed at the retainer body and the other end is fixed at the collar.

When the valve is operated to open, displacement of the predetermined angle generated by compression of the elastic member may be transferred to the valve via the retainer body and the valve cotter, thereby rotating the valve by the predetermined angle.

The valve cotter may include an elastic member fixedly inserted into an insertion groove formed at the upper exterior circumference of the valve. The retainer body may be formed with a first fixing groove where the one end of the elastic member is fixed. The collar may be formed with a second fixing groove where the other end of the elastic member is fixed. The elastic member may include a coil spring.

The present invention has advantages of preventing the one-side wear or the deformation or the leakage of gas due to an uneven contact between a valve and a valve seat by facilitating the rotation of the valve, as well as function as a retainer simultaneously, by applying the means for rotating valve. In addition, the present invention has advantages that the function of a retainer is applied to the means for rotating valve, and it is not necessary to add the function of a retainer separately, thus the manufacturing cost may be decreased.

The methods and apparatuses of the present invention have other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated herein, and the following Detailed Description, which together serve to explain certain principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view illustrating an exemplary valve train of an engine for a vehicle according to the present invention.

FIG. 2 is a cross-sectional view illustrating an exemplary valve train of an engine for a vehicle according to the present invention.

FIG. 3 is an enlarged view of the A portion of FIG. 2.

FIG. 4 is a front view of an elastic member which is applied to an exemplary valve train of an engine for a vehicle according to the present invention.

FIG. 5 is a cross-sectional view illustrating a state before the operation of an exemplary valve train of an engine for a vehicle according to the present invention.

FIG. 6 is a cross-sectional view illustrating a state after the operation of an exemplary valve train of an engine for a vehicle according to the present invention.

DETAILED DESCRIPTION

Reference will now be made in detail to various embodiments of the present invention(s), examples of which are illustrated in the accompanying drawings and described below. While the invention(s) will be described in conjunction with exemplary embodiments, it will be understood that present description is not intended to limit the invention(s) to those exemplary embodiments. On the contrary, the invention(s) is/are intended to cover not only the exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims.

The size and thickness of each constituent element shown in the drawings are given for convenience of the description, and the present invention is not necessarily limited to the drawing. To clearly express several parts or areas, the thickness of the parts is enlarged. Also, to clearly describe exemplary embodiments of the present invention, the parts which are not in relation to the description will be omitted.

FIG. 1 is a perspective view illustrating a valve train of an engine for a vehicle according to various embodiments of the present invention, and FIG. 2 is a cross-sectional view illustrating a valve train of an engine for a vehicle according to various embodiments of the present invention.

Referring to FIG. 1 and FIG. 2, a valve train 1 of an engine for a vehicle according to various embodiments of the present invention includes a rocker arm 7, which reciprocates up and down following the rotation of the cam shaft 5 where a cam 3 is installed, moves a valve bridge 9, and operates a valve 10 installed in a combustion chamber, which comprises a structure that prevents the one-side wear or the deformation due to an uneven contact between a valve and a valve seat by facilitating the rotation of the valve, as well as that functions as a retainer simultaneously.

FIG. 3 is an enlarged view of the A portion of FIG. 2, and FIG. 4 is a front view of an elastic member which is applied to a valve train of an engine for a vehicle according to various embodiments of the present invention.

Referring to FIG. 3 and FIG. 4, the valve train 1 of an engine for a vehicle according to various embodiments includes a means or a member for rotating valve 20.

The means or member for rotating valve 20 is interposed between the valve bridge 9 and the valve spring 11 at the upper part of the valve 10, which rotate the valve 10 with a predetermined angle when the valve 10 reciprocates. Here, the means for rotating valve 20 includes a valve cotter 30, a retainer body 40, a collar 50 and an elastic member 60.

The valve cotter 30 is engaged with the upper exterior circumference of the valve 10. Such valve cotter 30 may be made up of an elastic member fixed by being inserted into an insertion groove 13 which is formed at the upper exterior circumference of the valve 10.

The retainer body 40 is engaged with the exterior circumference of the valve cotter 30, and is formed with a first fixing groove 41 where an end of the elastic member 60 is fixed.

The collar 50 is disposed at the exterior circumference of the retainer body 40 with being spaced apart and its lower end is fixedly supported by the valve spring 11, and is formed with a second fixing groove 51 where the other end of the elastic member 60 is fixed.

The elastic member 60 is interposed between the retainer body 40 and the collar 50, where an end is fixed at the first fixing groove 41 of the retainer body 40 and the other end is fixed at the second fixing groove 51, and includes a coil spring.

Referring to FIG. 4, when a compressive force occurs in the elastic member 60, the displacement from the point A to the point B occurs at an angle, and when the compressive force is released, the elastic member 60 returns from the point B to the point A. Since such an operation of the elastic member 60 according to the compressive force is known in the art, more detailed description will be omitted below.

That is, when the valve operates to open, the displacement of a predetermined angle generated by the compression of the elastic member 60 is transferred to the valve 10 via the retainer body 40 and the valve cotter 30, the means for rotating valve rotates the valve 10 with a predetermined angle.

Hereinafter, the operation of the valve train 1 of an engine for a vehicle including the above-described embodiments will be described.

FIG. 5 is a section view illustrating a state before the operation of the valve train of an engine for a vehicle according to various embodiments of the present invention, and FIG. 6 is a section view illustrating a state after the operation of the valve train of an engine for a vehicle according to various embodiments of the present invention.

Referring to FIG. 5 and FIG. 6, the valve train 1 of an engine for a vehicle according to various embodiments of the present invention operates, first, the rocker arm 7 is moved downward due to the rotation of the cam shaft 5 where the cam 3 is installed, then the valve bridge 9 connected to the rocker arm 7 is also moved downward, and the valve 10 connected to the valve bridge is operated by the movement of the valve bridge 9.

Then, the retainer body 40 which is connected with the valve 10 and the valve cotter 30 compresses the elastic member 60, and is moved downward by the operation of the valve simultaneously.

As described above, the elastic member 60 which is compressed by the retainer body 40 is displaced with a predetermined angle, and due to the displacement of the elastic member 60, the retainer body 40 is also rotated with a predetermined angle. That is, the valve 10 which is engaged with the retainer body 40 and valve cotter 30 is rotated by the rotation of the retainer body which is occurred by the displacement with a predetermined angle of the elastic member 60.

Accordingly, the valve train 1 of an engine for a vehicle according to various embodiments of the present invention may prevent the one-side wear or the deformation or the leakage of gas due to an uneven contact between a valve and a valve seat by facilitating the rotation of the valve, as well as function as a retainer simultaneously, by applying the means or member for rotating valve 20.

In addition, the function of a retainer is applied to the means for rotating valve, and it is not necessary to add the function of a retainer separately, thus the manufacturing cost may be decreased.

For convenience in explanation and accurate definition in the appended claims, the terms “upper” or “lower”, “up” and “down”, and etc. are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.

The foregoing descriptions of specific exemplary embodiments of the present invention have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teachings. The exemplary embodiments were chosen and described in order to explain certain principles of the invention and their practical application, to thereby enable others skilled in the art to make and utilize various exemplary embodiments of the present invention, as well as various alternatives and modifications thereof. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. 

What is claimed is:
 1. A valve train of an engine for a vehicle, comprising: a rocker arm that reciprocates up and down; a valve bridge that is moved by the rocker arm and operates a valve installed in a combustion chamber; a member for rotating valve interposed between the valve bridge and a valve spring disposed at an upper part of the valve, wherein the member for rotating valve rotates the valve by a predetermined angle when the valve reciprocates.
 2. The valve train of an engine for a vehicle of claim 1, wherein the member for rotating valve comprises: a valve cotter engaged with an upper exterior circumference of the valve; a retainer body engaged with an exterior circumference of the valve cotter; a collar spaced apart from an exterior circumference of the retainer body, wherein a lower end is fixedly supported by the valve spring; and an elastic member interposed between the retainer body and the collar, wherein one end is fixed at the retainer body and the other end is fixed at the collar.
 3. The valve train of an engine for a vehicle of claim 2, wherein when the valve is operated to open, displacement of the predetermined angle generated by compression of the elastic member is transferred to the valve via the retainer body and the valve cotter, thereby rotating the valve by the predetermined angle.
 4. The valve train of an engine for a vehicle of claim 2, wherein the valve cotter includes an elastic member fixedly inserted into an insertion groove formed at the upper exterior circumference of the valve.
 5. The valve train of an engine for a vehicle of claim 2, wherein the retainer body is formed with a first fixing groove where the one end of the elastic member is fixed.
 6. The valve train of an engine for a vehicle of claim 2, wherein the collar is formed with a second fixing groove where the other end of the elastic member is fixed.
 7. The valve train of an engine for a vehicle of claim 2, wherein the elastic member includes a coil spring. 